气象学报2012，Vol.70Issue(3)：479-491,13.
1-3月北极涛动对北半球热带太平洋和大西洋对流活动的可能影响
Possible influence of January-March Arctic Oscillation on the convection of tropical North Pacific and North Atlantic
摘要
Abstract
An analysis of detailed relationships between the January-February-March Arctic Oscillation and the convection in the tropical Pacific Ocean and the tropical Atlantic Ocean is presented based on the daily outgoing longwave radiation dataset and the monthly NCEP reanalysis datasets with the ENSO signals removed from all the datasets. The results indicate that a high (low) AO phase more likely accompanies with a stronger (weak) convection in the tropical Pacific Ocean and the tropical Atlantic Ocean. The correlations between the AO index and the tropical OLR in boreal winter show two pronounced negative correlation areas: one in the central Pacific Ocean, ranging between 13°-20°N, 160°E- 170°W and the other in the tropical Atlantic Ocean, covering 5° - 20°N, 15° - 70°W. The prominent positive correlation is also demonstrated in the precipitation field. The time-lag correlation analyses indicate that the correlation of the AO index with the OLR, the strong convection area, the intensity index and the mean precipitation is the strongest in the concorrent winter and the correlation weakens rapidly with time. At the same time, the lower tropospheric atmosphere circulation anomalies corresponding to the JFM AO index change significantly in the two regions. During positive AO winter, there is an anomalous atmospheric cyclone in the tropical Pacific Ocean while there are a meridional circulation convergence and a horizontal wind shear in the tropical Atlantic Ocean at 850 hPa. And the AO-related SSTs, particularly in the central ocean regions, are well reproduced by the simulation experiments of the ocean model LICOM, suggesting that the observed AO-related SSTs are mainly the response to atmospheric circulation changes. Meanwhile, the connections of AO-related SSTs with convection and precipitation activities are relatively weak. The changes in the atmospheric circulation are probably the main linkage among the AO and convection and precipitation in the tropical Pacific and Atlantic Ocean for January to March.关键词
北极涛动/对流活动/热带太平洋/热带大西洋Key words
Arctic Oscillation, Convection activity, Tropical Pacific Ocean, Tropical Atlantic Ocean分类
天文与地球科学引用本文复制引用
胡淼,龚道溢,王璐,周天军,张自银..1-3月北极涛动对北半球热带太平洋和大西洋对流活动的可能影响[J].气象学报,2012,70(3):479-491,13.基金项目
国家高技术研究发展计划(863计划)重点项目(2008AA121704)和国家科技支撑计划课题(2007BAC29B02). （863计划）
